Greedy intervals: choose the earliest finishing option to minimize resources

Greedy intervals: Return the minimum number of points needed so that every closed interval contains at least one chosen point.

Input: A JSON object { "intervals": [number, number][] }.

Output: A JSON integer minimum point count.

Constraints:

0 <= intervals.length <= 100000
Every interval satisfies start <= end
Intervals are closed, so a shared endpoint can cover both

Read one JSON value from stdin and print exactly one JSON-serialized answer to stdout with no extra text.

Difficulty: MEDIUM. Variant: 20. Expect follow-up questions about complexity, edge cases, and alternative approaches.

Practice context

This coding (algo) exercise trains prompt interpretation, explicit assumptions, a concrete response, and a concise explanation of the decisions made. It is marked medium difficulty.

The signed-in workspace provides the tools required by the round, such as recording, code

What this task practices

This coding (algo) exercise trains the same sequence expected in an interview: understand the prompt, make assumptions explicit, produce a concrete answer, and explain the decisions behind it. The task is marked medium difficulty. The private workspace adds the tools required by this round, such as recording, code execution, diagrams, evidence panels, or structured notes. It also preserves the attempt so later feedback can be compared with previous work. Evaluation is based on task-specific criteria and the candidate seniority selected in the preparation path. Public pages never expose the reference solution, hidden tests, evaluator instructions, or another candidate’s work.